From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>, daniele.varrazzo@gmail.com,
        pgsql-hackers@lists.postgresql.org
Subject: Re: Using PQexecQuery in pipeline mode produces unexpected Close
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Comments: In-reply-to Alvaro Herrera <alvherre@alvh.no-ip.org>
	message dated "Wed, 15 Jun 2022 20:26:33 +0200"
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Date: Wed, 15 Jun 2022 14:56:42 -0400
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Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> So, git archaeology led me to this thread
> https://postgr.es/m/202106072107.d4i55hdscxqj@alvherre.pgsql
> which is why we added that message in the first place.

Um.  Good thing you looked.  I doubt we want to revert that change now.

> Alternatives:
> - Have the client not complain if it gets CloseComplete in idle state.
>   (After all, it's a pretty useless message, since we already do nothing
>   with it if we get it in BUSY state.)

ISTM the actual problem here is that we're reverting to IDLE state too
soon.  I didn't try to trace down exactly where that's happening, but
I notice that in the non-pipeline case we don't go to IDLE till we've
seen 'Z' (Sync).  Something in the pipeline logic must be jumping the
gun on that state transition.

			regards, tom lane